1/* $NetBSD: brk.S,v 1.9 2000/06/26 06:25:45 kleink Exp $ */ 2 3/* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * from: Header: brk.s,v 1.3 92/06/25 12:56:05 mccanne Exp 40 */ 41 42#include <machine/asm.h> 43#if defined(SYSLIBC_SCCS) && !defined(lint) 44#if 0 45 .asciz "@(#)brk.s 8.1 (Berkeley) 6/4/93" 46#else 47 RCSID("$NetBSD: brk.S,v 1.9 2000/06/26 06:25:45 kleink Exp $") 48#endif 49#endif /* SYSLIBC_SCCS and not lint */ 50 51#include "SYS.h" 52 53 .globl CURBRK 54 .globl _C_LABEL(__minbrk) 55 .globl _end 56 57#ifdef WEAK_ALIAS 58WEAK_ALIAS(brk, _brk) 59#endif 60 61 .data 62_C_LABEL(__minbrk): 63 .long _end ! lower brk limit; also for gmon code 64 .text 65 66ENTRY(_brk) 67#ifdef PIC 68 PIC_PROLOGUE(%o5,%o4) 69 ld [%o5 + _C_LABEL(__minbrk)], %o4 70 ld [%o4], %o1 ! %o1 = minbrk 71 cmp %o1, %o0 ! if (minbrk > %o0) 72 bg,a 0f 73 mov %o1, %o0 ! %o0 = minbrk 740: 75 mov %o0, %o2 ! save argument to syscall 76 mov SYS_break, %g1 77 t ST_SYSCALL 78 bcc,a 1f 79 ld [%o5 + CURBRK], %o4 80 ERROR() 811: 82 retl ! success, return 0 & record new break 83 st %o2, [%o4] 84#else 85 sethi %hi(_C_LABEL(__minbrk)), %o1 ! %o1 = minbrk 86 ld [%o1 + %lo(_C_LABEL(__minbrk))], %o1 87 cmp %o1, %o0 ! if (minbrk > %o0) 88 bg,a 0f 89 mov %o1, %o0 ! %o0 = minbrk 900: 91 mov %o0, %o2 ! save argument to syscall 92 mov SYS_break, %g1 93 t ST_SYSCALL 94 bcc,a 1f 95 sethi %hi(CURBRK), %g1 96 ERROR() 971: 98 retl ! success, return 0 & record new break 99 st %o2, [%g1 + %lo(CURBRK)] 100#endif 101